The transferrin receptor contains at lease one O-glycan and three N-glycans which possess high mannose or complex structures. The unglycosylated form of the transferrin receptor has been found not to be functional. Dr. John Lucas will test the hypothesis that glycosylation is vital for correct folding and transport of the transferrin receptor to the cell surface and in the binding of transferrin. Site-directed mutagenesis will be used to test the contributions of the N- and O-glycosylation sites the folding and transport of the receptor. Characterization of the oligosaccharides will be achieved by a variety of protein and carbohydrate chemical techniques and by lectin affinity chromatography and MALDI-TOF-MS.